Condensed Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014
Operating activities:
Net loss	$ (10,922)	$ (14,854)
Adjustments to reconcile net loss to net cash used in operating activities:
Amortization of intangible assets	1,687	1,687
Depreciation and amortization of property and equipment	1,080	2,078
Impairment of property and equipment	0	1,841
Change in the fair value of assets held for sale	0	755
Gain on disposal of property and equipment	(5)	(78)
Income tax benefit related to marketable securities	(463)	(249)
Gain on sale of Hungarian subsidiary	0	(760)
Stock-based compensation	2,536	2,575
Amortization of premium on marketable securities	0	2
Changes in operating assets and liabilities:
Accounts receivable, net	1,076	2,513
Inventories, net	427	(476)
Prepaid expenses and other current assets	221	(703)
Other assets	19	11
Accounts payable	(2,964)	(631)
Accrued compensation	(331)	(1,498)
Other accrued liabilities	(984)	1,002
Deferred revenue	660	446
Net cash used in operating activities	(7,963)	(6,339)
Investing activities:
Purchase of property and equipment	(240)	(111)
Proceeds from maturities of marketable securities	0	3,000
Proceeds from sale of Hungarian subsidiary, net of selling costs	0	1,500
Proceeds from the sale of assets held for sale	0	4
Proceeds from sale of property and equipment	5	187
Increase in restricted cash	(75)	0
Net cash provided by (used in) investing activities	(310)	4,580
Financing activities:
Proceeds from exercises of options to purchase common stock	195	62
Taxes paid related to net share settlement of equity awards	(1,811)	(343)
Net cash used in financing activities	(1,616)	(281)
Net decrease in cash and cash equivalents	(9,889)	(2,040)
Cash and cash equivalents at the beginning of the period	26,487	22,130
Cash and cash equivalents at the end of the period	$ 16,598	$ 20,090